Racing 7 min
Sub-4 marathon training plan: a 16-week approach
Running a marathon under four hours means holding roughly 5:41 per kilometre — about 9:09 per mile — for the full 26.2. For most runners that takes around 16 weeks of structured training from a solid base: three to five runs a week, a long run that builds toward 20 miles, and weekly work at goal pace. Here's how the block fits together, and where an adaptive plan keeps it realistic when life interrupts.
What sub-4 actually requires
Four hours is 5:41/km or 9:09/mile, unbroken. To hold that comfortably on race day you want to have trained a bit faster in shorter doses, and to have run enough long runs that 20 miles feels routine. A realistic starting point is being able to run a half marathon around 1:50 or comfortably cover 10 miles — if you're not there yet, build a base first rather than forcing the block.
The 16-week shape
Think of the block in four phases, each about four weeks: base, build, peak, taper. Volume rises through base and build, the long run stretches through peak, and everything comes down in the final two to three weeks so you arrive fresh.
- Weeks 1–4 (Base): rebuild consistent mileage; long run 10–13 miles; all easy running plus light strides.
- Weeks 5–8 (Build): introduce weekly goal-pace work; long run to 15–16 miles; add a tempo session.
- Weeks 9–13 (Peak): longest runs of 18–20 miles, some with goal-pace finishes; highest weekly volume.
- Weeks 14–16 (Taper): cut volume ~40% while keeping short sharp goal-pace touches; race in week 16.
The sessions that matter most
Three workouts do the heavy lifting. The long run builds the endurance to hold pace late. The tempo or threshold run raises the speed you can sustain without fatiguing. And goal-pace segments — chunks of the long run run at 5:41/km — teach your body and your head what race effort feels like. Everything else should be genuinely easy, which is where most sub-4 attempts go wrong: too many medium-hard runs, not enough recovery.
Weekly mileage guidance
Most runners hit sub-4 on 30–45 miles a week at peak, though it can be done on less with quality sessions and consistency. The number matters less than the progression: build no more than about 10% a week, and take a lighter recovery week every third or fourth week so the load actually turns into fitness rather than injury.
Why an adaptive plan helps for sub-4
A 16-week block never runs clean. RunV takes a goal like sub-4, sets the paces, and rebuilds the schedule around your real runs — so a missed long run or a rough week re-ramps instead of derailing the target. It also shows a predicted finish that updates as your training banks fitness, so you know whether sub-4 is on or whether the goal needs adjusting before race day.
FAQ
- What pace is a sub-4 marathon?
- About 5:41 per kilometre, or 9:09 per mile, held for the whole 26.2 miles. Training a little faster in tempo and goal-pace sessions makes that race pace feel sustainable.
- How many miles a week for a sub-4 marathon?
- Most runners manage it on 30–45 miles a week at peak. Consistency and quality sessions matter more than raw volume — building gradually and recovering well beats chasing big numbers.
- Is 16 weeks long enough to train for a sub-4 marathon?
- Yes, from a reasonable base — roughly a 1:50 half or comfortable 10-milers. If you're starting further back, build base fitness first so the 16-week block starts from the right place.
Train smarter
RunV turns this thinking into your plan — adaptive coaching that rebuilds after every run.
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